PT-2026-36415 · Linux · Linux Kernel

Published 2026-05-01 · Updated 2026-05-11 · CVE-2026-31780

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A heap buffer overflow occurs in the wilc1000 WiFi driver due to an integer overflow in the SSID scan buffer size calculation. The variable valuesize is declared as a u8 (an 8-bit unsigned integer), but it accumulates the total length of all SSIDs to scan. Since each SSID can contribute up to 33 bytes and there can be up to 10 SSIDs, the total can reach 330 bytes, which wraps around to 74 when stored in a u8. Consequently, kmalloc() allocates only 75 bytes, while a subsequent memcpy() operation writes up to 331 bytes, leading to a 256-byte overflow.

Recommendations Update the Linux kernel to a version where the valuesize variable has been widened from u8 to u32 to accommodate the full range of the buffer size.

Fix

Memory Corruption

Weakness Enumeration

CWE-787

Related Identifiers

CVE-2026-31780

ECHO-6161-7139-EE2F

Affected Products

Linux Kernel

References · 18

• https://git.kernel.org/stable/c/9907ac9b9a18b92fc34b9e4cb9e10f208dc1d3f7 · Patch
• https://ubuntu.com/security/CVE-2026-31780 · Vendor Advisory
• https://git.kernel.org/stable/c/0c7f21d8bd2f93998b72b7a7f93152336aeca4dd · Patch
• https://git.kernel.org/stable/c/d049e56b1739101d1c4d81deedb269c52a8dbba0 · Patch
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-31780 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-31780 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-31780 · Security Note
• https://git.kernel.org/stable/c/bfbddeadd4779651403035ee177ae2f22f9f5521 · Patch
• https://osv.dev/vulnerability/BELL-CVE-2026-31780 · Vendor Advisory
• https://git.kernel.org/stable/c/c97b2a00059608592ad0d86fbb813a4f8cf9464b · Patch
• https://git.kernel.org/stable/c/34a23fd9ddd683a03c7e8cc0ceded3e59e354b99 · Patch
• https://git.kernel.org/stable/c/d8388614de613c28eeb659c10115060a83739924 · Patch
• https://git.kernel.org/stable/c/549f02d8ec94d39092ab6d9b103d0d6783a4b024 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-31780 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-31780 · Security Note